Field of the Invention
The invention relates to a process for disposing of waste, in which the waste is carbonized at low temperatures, to develop carbonization gas and solid carbonization residue, the carbonization gas is burned and the carbonization residue is divided into a coarse and a fine fraction. The invention also relates to an apparatus for disposing of waste, having a waste feed device that discharges into a carbonization drum from which a carbonization gas outlet line and a carbonization residue outlet line discharge, the carbonization gas outlet line is connected to a combustion chamber which has a flue gas outlet, and the carbonization residue outlet line is connected to a separator which has outlet lines for a coarse and a fine fraction.
Such a process and such an apparatus for thermal waste disposal are disclosed in European Patent 0 302 310 B1, corresponding to U.S. Pat. No. 4,878,440. That apparatus has a carbonization drum into which the waste to be disposed of is introduced. The waste is carbonized at low temperatures there and carbonization gas and a solid carbonization residue are produced. The carbonization gas is supplied directly to a combustion chamber. The carbonization residue is divided into a coarse and a fine fraction and the fine fraction, if appropriate after a grinding operation, is fed into the combustion chamber as is the carbonization gas. The materials being fed in are burned there at high temperature and molten slag is formed which is discharged into a waterbath. Flue gas which is also produced is subjected to flue gas purification.
German Published, Non-Prosecuted Application DE 38 28 534 A1 discloses a process for thermal waste disposal in which, after the low-temperature carbonization operation, some of the carbonization residue is ground and then gasified as dust. A gasifier supplies a crude gas which drives a turbine and a gasifying residue which is burnt in a high-temperature furnace. The gasifier only serves to generate the crude gas. All of the solid matter must be fed from the gasifier to the high-temperature furnace. The apparatus, up to the high-temperature furnace, must therefore be dimensioned to be just as large as if no gasifier were connected in between the low-temperature carbonization device and the high-temperature furnace.